One drunk driving conviction has already been thrown out because evidence could have been tainted in the Nassau County Police Crime Lab.
The lab was shut down last month after revelations supervisors may have failed to disclose inaccurate testing.
It now looks like many more cases could be potentially thrown out, and convictions overturned, even some high profile ones that involve murder or manslaughter charges.
Remember Kayla Gerdes? She's the 18-year-old charged with driving high on drugs, running over and killing 69-year-old Rebecca Twine, who was mowing her West Hempstead lawn last April.
Gerdes all but confessed to the horrific crime as news cameras were rolling, she even admitted to taking drugs.
"It was a mistake I'm sorry it was prescription drugs." Kayla shouted last April.
Her attorney John Lewis has always maintained Gerdes was sober at the time of the crash.
"Just because she is sorry that somebody lost there life doesn't mean she is admitting to that fact that she was intoxicated at the time she was operating the vehicle." said Lewis.
Back then, Lewis called into question how the Nassau County Crime Lab handled blood evidence taken from Gerdes.
Now in hearings he is trying to get that damaging evidence suppressed, evidence that shows Gerdes had narcotics in her system.
The District Attorney is not backing down. Nassau DA spokeswoman Carole Trottere told PIX 11 News, "The defendant's blood was tested for drugs at NMS Laboratory in Pennsylvania - not the police crime lab."
But Lewis is not challenging that.
"Part of the report is that they had problems with evidence collection and storage, which means that we don't know that the evidence taken from a certain defendant is actually the evidence that is being analyzed," said Lewis.
"That's where the real problem comes in because I don't care how many times you re-test a sample. If you can't establish a chain of custody to the actual defendant it's supposed to be, then it's not admissible."
Gerdes is charged with manslaughter and in jail awaiting trial.Copyright © 2014, Los Angeles Times